You think about it too much, you can play poker anytime, if there are other players. I`m from South Europe, it`s early morning but guess what, most of the poker tables are empty now. Usually free roll tournaments have some players and if there is some tournament I play it. Because of the lack of players, in the morning I like to play dices, slots, like some brain workout, I don`t gamble with a lot of money in the morning, except in one case, if I won big last night. I think that evening and night are the best for gambling too, but I don`t care what time is it when I`m on vocation and I have free days, that change a picture a lot. When person have a lot of free time, anytime is good for gambling if you`re in favor of it.
have any exact period of day, it can start anytime and will last for so long, even last for the whole day as long as all of you are enjoying.